1. Field of the Invention
This invention relates to resistance elements for variable resistors, and more particularly, to zig-zag type resistance elements formed on insulating base plates by means of printing or by vacuum evaporation.
2. Description of the Prior Art
As illustrated in FIG. 1, a resistance element 3 for a known form of conventional variable resistor is generally formed in zig-zag fashion within the sliding range of a slider in order to be able to obtain a large variation ratio of resistance value. In such resistors, the slider is moved linearly along the center portion of the resistance element 3, whereby the resistor will exhibit a resistance variation and, when used in a potentiometer, an output voltage variation represented by a graph that varies in the form of a step, as shown by a full line in FIG. 2, thus resulting in the degradation of the resolution of the output voltages. In addition, the sliding motion of the slider is not smooth because the slider does not move continuously over the surface of resistance element 3, thus also resulting in the generation of noises and the shortening of the life of the resistor.